FIELD OF THE INVENTION
[0001] The present invention relates to landscape trimmers, and more particularly, to string
heads for landscape trimmers.
BACKGROUND OF THE INVENTION
[0002] Landscape trimmers are used to cut grass and weeds, and are often used to edge around
trees, near fences and walls, and along landscape borders. Conventional landscape
trimmers include an elongated shaft with a rotating element or gear head near the
end of the elongated shaft, and a spool or string head is attached to the gear head.
Typically, the string head includes a monofilament line (i.e., trimmer line) or other
cutting device that is rotated by the gear head for cutting and trimming along landscaped
areas, fences, and walls.
[0003] One type of string head is a bump-feed string head, which includes two relatively
long lengths of trimmer line that are wrapped around a spool. A user bumps the string
head on the ground when the exposed trimmer line becomes too short or worn in order
to feed additional trimmer line out of the string head. Another type of string head
is a fixed line string head. For a fixed line string head, the user feeds, typically
two, discrete lengths of trimmer line (generally around 12 to 18 inches) through the
string head. The trimmer lines are each held adjacent one end by the string head and
the opposite ends of the trimmer lines are exposed for cutting. When the trimmer line
becomes too short or wears, the user feeds a new piece of trimmer line through the
string head.
[0004] An object of the invention is to mitigate or obviate to some degree one or more problems
associated with known landscape trimmers.
SUMMARY
[0005] In one construction, the invention provides a landscape trimmer including a motor,
an output shaft driven by the motor, and a trimmer head coupled to the output shaft
and rotatable with the output shaft. The trimmer head is operable in a fixed line
configuration and a bump-feed configuration. The trimmer head includes, a base including
a cup having a top wall and a substantially cylindrical side wall that defines an
aperture, and the base including a collar extending axially from the top wall of the
cup and for coupling the trimmer head with the output shaft. A fixed line head is
at least partially received within the cup of the base when the trimmer head is in
the fixed line configuration. The fixed line head includes at least one channel having
an inlet portion substantially aligned with the aperture of the base, an outlet portion,
and a clamping member. A bump-feed spool is at least partially received within the
cup of the base when the trimmer head is in the bump-feed configuration. The bump-feed
spool includes a body and a trimmer line wrapped around the body, the trimmer line
extending through the aperture in the side wall of the base when the bump-feed spool
is received by the base.
[0006] The trimmer head may comprise a bump-knob, wherein the bump-knob retains the fixed
line head within the cup when the trimmer head is in the fixed line configuration
and retains the bump-feed spool within the cup when the trimmer head is in the bump-feed
configuration. The bump-knob may be removably coupled to the output shaft.
[0007] The fixed line head may include a base member that at least partially defines the
channel and a cover removably coupled to the base member. The cover may at least partially
define the channel. The cover may include an aperture substantially aligned with the
output portion of the channel. The aperture defined by the side wall of the base may
be generally U-shaped and includes an open end. The base may include a plurality of
stops extending radially inwardly from the side wall.
[0008] The fixed line head may include a plurality of apertures extending axially therethrough,
the apertures receiving the stops when the fixed line head is received in the base
to align the inlet portion with the aperture defined by the side wall. The stops may
allow the bump-feed spool to rotate a predetermined angular distance with respect
to the base upon contacting the trimmer head with an external surface.
[0009] In another construction, the invention provides a trimmer head for use on a landscape
trimmer having an output shaft. The trimmer head includes a base having a cup with
a top wall and a substantially cylindrical side wall that defines an aperture, where
the top wall and the side wall define an inner cavity of the base, and the base includes
a collar extending from the top wall of the cup and away from the inner cavity. The
collar for coupling with the output shaft of the landscape trimmer for rotation therewith.
The trimmer head also includes a fixed line head received within the inner cavity
of the base and coaxial with the output shaft, the fixed line assembly including a
base member and a cover removably coupled to the base member, the base member and
the cover defining a channel including an inlet portion substantially aligned with
the aperture of the base, an outlet portion, and a clamp member configured to retain
a portion of a trimmer line within the channel. The trimmer head also includes a bump-knob
coupled to a free end of the output shaft to retain the fixed line head within the
base.
[0010] The aperture may be substantially U-shaped and includes an open end.
[0011] The base may include a plurality of stops positioned within the inner cavity and
extending radially inwardly from the side wall.
[0012] The base member may include a plurality of apertures extending axially through the
base member, each of the apertures receiving one of the stops when the fixed line
head is received in the base to align the inlet portion with the aperture defined
by the side wall.
[0013] The cover may include a plurality of apertures extending axially through the cover,
each of the apertures receiving one of the stops when the fixed line head is received
in the base to align the inlet portion with the aperture defined by the side wall.
[0014] The trimmer head may comprise a bump-feed spool for being received by the base when
the fixed line head is removed from the base, the bump-feed spool including a body
and a trimmer line wrapped around the body, the trimmer line extending through the
aperture in the side wall of the base when the bump-feed spool is received by the
base. The bump-knob may be coupled to a free end of the output shaft to retain the
bump-feed spool within the base.
[0015] The base may include a plurality of stops positioned within the inner cavity and
extending radially inwardly from the side wall.
[0016] In yet another construction, the invention provides a fixed line head for use in
a trimmer head. The trimmer head includes a base having a cup with a top wall and
a substantially cylindrical side wall defining an aperture, the top wall and the side
wall defining an inner cavity, and the base also including a plurality of stops positioned
within the cavity and extending radially inwardly from the side wall. The fixed line
head includes a base member, a first channel at least partially defined by the base
member, the first channel including a first inlet portion, a first outlet portion,
and at least one clamp member able to retain at least a portion of a trimmer line
within the first channel. The fixed line head also includes a second channel at least
partially defined by the base, the second channel including a second inlet portion,
a second outlet portion, and at least one clamp member able to retain at least a portion
of a trimmer line within the second channel. The fixed line head also includes a plurality
of recesses defined by the base member and extending axially therethrough, the recesses
receiving the stops when the fixed line head is received in the base to further align
one of the first and the second inlet portions with the aperture defined by the side
wall.
[0017] In a further construction, the invention provides a method of converting a trimmer
head between a fixed line configuration and a bump-feed configuration. The trimmer
head includes a base having a side wall defining a first aperture and an inner cavity,
one of a spool and a fixed line head at least partially received within the cavity,
and a bump-knob to retain the one of the spool and the fixed line head within the
inner cavity. The method includes removing the bump-feed knob, removing the one of
the spool and the fixed line head from the inner cavity, introducing the other of
the spool and the fixed line head into the inner cavity, and introducing the bump-knob
to retain the other of the spool and the fixed line head within the inner cavity.
[0018] The method may comprise inserting a first end of a trimmer line into the first aperture
and the fixed line head to be retained within the fixed line head by a clamping member.
[0019] The fixed line head may include a channel, the channel having an inlet portion, an
outlet portion, and a clamping member, and further wherein positioning the fixed line
head into the inner cavity includes aligning the inlet portion with the first aperture.
[0020] The summary of the invention does not necessarily disclose all the features essential
for defining the invention; the invention may reside in a sub-combination of the disclosed
features.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a perspective view of a string head trimmer according to one construction
of the invention and in a bump-feed configuration coupled to an output shaft of a
powered trimmer.
[0022] FIG. 2 is a section view of the string head trimmer taken along lines 2--2 of FIG.
1.
[0023] FIG. 3 depicts the string head trimmer of FIG. 2 with a spool in an alternate position.
[0024] FIG. 4 is a perspective view of the string head trimmer of FIG. 2.
[0025] FIG. 5 is a perspective view of a portion of the string head trimmer of FIG. 1 with
a bump-knob removed and the bump-feed spool exploded from a string head.
[0026] FIG. 6 is a perspective view of the string head trimmer in a fixed line configuration
and coupled to the output shaft of a powered trimmer.
[0027] FIG. 7 is a section view of the string head trimmer taken along lines 7--7 of FIG.
6.
[0028] FIG. 8 is a perspective view of the string head trimmer of FIG. 7.
[0029] FIG. 9 is a top perspective view of a string head of the string head trimmer of FIG.
6 with the output shaft removed.
[0030] FIG. 10 is a perspective view of the string head with a cover removed for clarity.
[0031] FIG. 11 is side view of a fixed line head.
[0032] FIG. 12 is section view of the fixed line head taken along lines 12-12 of FIG. 11.
[0033] FIG. 13 is a top view of a base member of the fixed line head.
[0034] FIG. 14 is perspective view of the base member of the fixed line head.
[0035] FIG. 15 is top view of the cover of the fixed line head.
[0036] FIG. 16 is a bottom view of the cover of the fixed line head.
[0037] Before any constructions of the invention are explained in detail, it is to be understood
that the invention is not limited in its application to the details of construction
and the arrangement of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other constructions and of
being practiced or of being carried out in various ways. Also, it is to be understood
that the phraseology and terminology used herein is for the purpose of description
and should not be regarded as limiting.
DETAILED DESCRIPTION
[0038] FIGS. 1 and 6 illustrate a trimmer head or string head 20 for use on a powered trimmer
22 that is used as either a bump-feed string head or a fixed line string head. The
powered trimmer 22 includes an output shaft 23 (FIGS. 2 and 7) driven by a motor,
such as a two-cycle gas engine, an electric motor, or the like. As illustrated in
FIGS. 1-10, the string head 20 defines a central axis 26 and includes a base 24 couplable
to and rotatable with the output shaft 23. The base 24 is able to receive any one
of a bump-feed spool 72 and a fixed line head 86 (described below and shown in FIGS.
5 and 11, respectively). The string head 20 also includes a bump-knob 30 removably
coupled to the output shaft 23 to retain any one of the bump-feed spool and the fixed
line trimmer assembly within the base 24. In other constructions, the bump-knob 30
may be coupled directly to the base 24.
[0039] Referring to FIGS. 2-5, the base 24 includes a cup 32 and a collar 36 that extends
from the cup 32. As best seen in FIGS. 2 and 4, the base 24 includes a hex shaped
aperture 40 extending through the cup 32 substantially co-axial with the central axis
26. The aperture 40 is configured to receive a hexagonal connector portion 34 of the
output shaft 23 and transmit torque from the output shaft 23 to the base 24. In a
further construction, the aperture 40 and the connector portion 34 of the output shaft
23 have other shapes or connection features for interfacing with each other to transmit
torque.
[0040] With continued reference to FIGS. 2-5, the cup 32 includes a top wall 44 and a cylindrical
side wall 46 that extends axially downwardly from the top wall 44 to define an inner
cavity 45. The collar 36 extends axially away from the top wall 44 in an opposite
direction and away from the inner cavity 45. The side wall 46 defines a pair of opposed
apertures 50, which are U-shaped in the illustrated construction. In the illustrated
construction, inserts 54, 58 are positioned within one of the apertures 50. Each of
the inserts 54, 58 includes a tapered aperture 60, 62 and a slot 66, 68, respectively.
[0041] Referring to FIGS. 2, 3, 5, and 10, the cup 32 includes a first set of stops 69 (only
one of which is shown in FIG. 5) and a second set of stops 70 positioned within the
inner cavity 45 extending radially inwardly from the side wall 46. In the illustrated
construction, the stops 69 extend axially downward from the top wall 44, while the
stops 70 are spaced a distance from the top wall 44 to form a gap 71 therebetween
and extend axially beyond the stops 69 toward a bottom edge 88 of the base 24. In
the illustrated construction, the stops 69, 70 are circumferentially spaced apart
from adjacent stops 69, 70 at least a distance substantially corresponding to an arcuate
width of tabs 74 of the spool 72, as described below. In the illustrated construction,
the cup 32 includes six equally spaced stops 69 along the inner surface of the side
wall 46. In addition, the cup 32 includes four stops 70 positioned between adjacent
stops 69, with two stops 70 being omitted proximate the recesses 50. In further constructions,
each set of stops 69, 70 may include more or less stops dependent upon the particular
embodiment.
[0042] The string head 20 is configured for use in either a bump-feed configuration (for
example, with a bump-feed spool 72) or a fixed line configuration (for example, with
a fixed line head 86). Referring to FIGS. 1-5, when the string head 20 is used in
the bump-feed configuration, the bump-feed spool 72 is positioned within the cup 32
of the base 24. While in the cup 32, the spool 72 is moveable between a first position,
in which a top wall 80 of the spool 72 is spaced a first axial distance from the top
wall 44 (FIG. 3), and a second position, in which the top wall 80 is spaced a second
axial distance from the top wall 44 (FIG. 2). In the illustrated construction, the
second axial distance is greater than the first axial distance. A spring 82 is seated
about the output shaft 23 and between the spool 72 and the top wall 44 of the base
24 to bias the spool 72 to the second position.
[0043] The spool 72 includes a body 75 defining a first winding recess 73, about which a
first string line 76 is wound, and a second winding recess 77, spaced a distance from
the first winding recess 73 and separated by a radially extending wall 83, about which
a second string line 78 is wound. The spool 72 also includes a plurality of tabs 74
(i.e., six in the illustrated construction) extending radially outwardly from the
top wall 80 and spaced along a perimeter of the wall 80. The spool 72 includes a lower
lip 79 extending radially outwardly from the body 75 of the spool 72, the lip 79 defining
a set of slots 81, 81' (FIG. 5). The spool 72 also defines a central recess 84 configured
to receive at least a portion of the output shaft 23. An annular groove 85, concentric
with the central recess 84, provides a seat for the biasing spring 82. In the illustrated
construction, when the string head 20 is assembled with the bump-feed spool 72, the
lower lip 79 contacts the bottom edge 88 of the side wall 46 to limit the distance
the spool 72 may be biased into the cavity 45. In the illustrated construction, the
spool 72 includes a plurality of reinforcing ribs 87 to prevent flexing and warping
of the body 75.
[0044] The slots 81, 81' of the spool 72 correspond to the first and second slots of the
outer wall 66, 68, such that when the string head 20 is assembled with the spool 72
the slots 66, 68 are substantially aligned with the slots 81, 81'. In the illustrated
construction, the slots 81, 81' are generally T-shaped so that the ends of the first
and second trimmer lines 76, 78 may be secured within the slots 81, 81' when the spool
72 is removed from the cavity 45. Further, the slots 81, 81' prevent the first and
second trimmer lines 76, 78 from un-coiling from the spool 72 during storage outside
the base 24. When the spool 72 is positioned within the cup 32, the slots 81, 81'
provide a continuous path, collectively with slots 66 and 68, which allows a user
to manually move the ends of the first and second trimmer lines 76, 78 from a secured
position within the slots 81, 81' to a working position within the tapered apertures
60, 62 without removing the spool 72 from the base 24.
[0045] To assemble the string head 20 for use in a bump-feed configuration, the spool 72
is loaded into the base 24 by axially introducing the spool 72 into the cavity 45.
The spool 72 is rotated with respect to the cup 32 to align the slots 66, 68 of the
cup with the slots 81, 81' of the spool 72. Once aligned, the user may manually maneuver
the trimmer lines 76, 78 through the slots 81, 81'of the spool 72 and through the
slots 66, 68 of the cup 32, and into the corresponding apertures 60, 62, respectively.
Once the spool 72 is positioned within the cavity 45, the spool 72 is secured to the
cup 32 by the bump-knob 30.
[0046] Referring to FIGS. 2-4, the bump-knob 30 includes a body 89 and a fastener 91 1 threadably
received within the output shaft 23. The body 89 is axially moveable along the fastener
91 and contacts either the spool 72 or the fixed line head 86 (depending upon the
current configuration). The fastener 91 limits the axial distance the body 89 may
move away from the base 24, thereby maintaining any one of the spool 72 and the fixed
line head 86 within the cavity 45. When the string head 20 is in the bump-feed configuration,
the body 89 moves axially along the fastener 91 and contacts the spool 72 to move
the spool 72 between the first and second positions.
[0047] During operation of the string head 20 in the bump-feed configuration, the spool
72 is biased into the second position by the spring 82. In the second position, the
tabs 74 engage the stops 70 of the base 24 such that the spool 72 rotates with the
base 24. In this mode, ends of the first and second trimmer lines 76, 78 extend from
the apertures 60, 62 to cut vegetation.
[0048] To feed additional trimmer line from the string head 20, the head 20 is "bumped"
or pressed against an external surface (e.g., the ground). During operation, the centrifugal
force from the ends of the first and second trimmer lines 76, 78 create a moment about
the spool 72 urging the spool 72 to rotate with respect to the base 24. The motion
is restricted by the second set of stops 70 when the spool is in the first position.
When the bump-knob 30 contacts the external surface (e.g., during a "bump"), the bump
knob 30 moves axially upwardly along the fastener 91, thereby contacting and overcoming
the bias of spring 82 to push the spool 72 towards the top wall 44 and into the first
position (FIG. 3). In the first position, the tabs 74 no longer contact the second
set of stops 70 and the spool 72 rotates with respect to the base 24. Therefore, the
tabs 74 pass through the gaps 71 formed between the stops 70 and the wall 44 allowing
more trimmer line 76, 78 to be fed from the spool 72 until the tabs 74 contact one
of the stops 69 and rotation of the spool 72 is once again restricted. Once bump-knob
30 is no longer contacting the ground, the bump-knob returns to an initial position
and the spool 72 is biased axially away from the wall 44 by the spring 82 and back
into the second position. In the second position, the tabs 74 no longer contact the
stops 69 and the spool 72 rotates past the stops 69 until the tabs 74 engage one of
the stops 70. Generally, each bumping motion of the bump-knob 30 rotates the spool
72 a predetermined angular amount with respect to the base 24 to release a length
of both the first trimmer line 76 and the second trimmer line 78 through the respective
apertures 60, 62.
[0049] As discussed above, the string head 20 is also configured for use in a fixed line
configuration (for example, with the fixed line head 86). Referring to FIGS. 6-16,
when the string head 20 is used in the fixed line configuration, the fixed line head
86 is positioned within the cup 32 of the base 24. In use, a user can switch between
the bump-feed configuration and the fixed line configuration by removing the spool
72 (FIG. 5) from the cavity 45 of the base 24 and inserting the fixed line head 86
(FIGS. 11-16) into the cavity 45.
[0050] Referring to FIGS. 10-16, the fixed line head 86 includes a base member 90 and a
cover 28 coupled together to partially define a first line retainer 94 and a second
line retainer 94'. The first and second line retainers 94, 94' are substantially the
same; therefore, like components have been given like reference numbers with the exception
of a prime symbol to designate the second line retainer 94' and its components (only
the first line retainer 94 will be described in detail). While the illustrated fixed
line head 86 includes the two line retainers 94, 94', in other constructions the fixed
line head 86 may include one or more than two line retainers.
[0051] Referring to FIG. 13, the line retainer 94 includes an inlet end portion 98, an outlet
end portion 102, a channel 110 extending between the end portions 98, 102, and a clamping
member 118 for engaging the trimmer line (not shown). In the illustrated construction,
the channel 110 of the line retainer 94 is at least partially defined by walls 106
that are integrally formed with the base member 90 and at least partially defined
by ribs 112 formed in the cover 28, which are shown and described below with respect
to FIG. 12. The walls 106 are spaced apart such that a distance between the walls
106 decreases from the inlet end portion 98 toward the outlet end portion 102. A ramp
114 is formed integrally with the base member 90 and positioned proximate the outlet
end portion 102 to direct the trimmer line out a recess 156 formed in the cover 28.
[0052] Referring to FIGS. 13 and 14, the clamping member 118 of the line retainer 94 allows
the trimmer line to travel in a single direction 176 and prevent removal of the trimmer
line from the respective aperture 60, 62 of the string head 20. The clamping member
118 includes a biasing member 120, or spring, that biases the clamping member 118
towards the opposing wall 106, a ramped surface 122, teeth 124, and an elongated slot
126. A post 130 extending from the base member 90 is received by the slot 126 to guide
and limit movement of the clamping member 118 with respect to the base member 90.
Further, the configuration and spacing between the walls 106 also guide and limit
movement of the clamping member 118. In the illustrated construction, the spring 120
is positioned between one of the walls 106 and the clamping member 118 to bias the
clamping member 118 in the direction of arrow 134 towards the opposite wall 106 and
into engagement with the trimmer line (not shown) placed in the line retainer 94.
In the illustrated construction, when secured within the line retainer 94, the trimmer
line is clamped between the gripping teeth 124 of the clamping member 118 and the
wall 106. However in other constructions, the clamping member 118 may include a plurality
of clamps retaining the trimmer line therebetween. In yet other constructions, the
clamping member 118 may be pivotable in nature.
[0053] The base member 90 of the fixed line head 86 has a generally cylindrical perimeter
surface 138 and an outer diameter substantially corresponding to an inner diameter
of the side wall 46 of the base 24. The base member 90 is shaped to be received within
the cup 32 of the base 24, as illustrated in FIG. 10. Recesses 142 are formed in the
outer surface 138 of the base member 90, and each recess 142 corresponds to and is
configured to receive one of the stops 69, 70 of the string head base 24 such that
the base member 90 of the fixed line head 86 rotates with the string head 20.
[0054] Referring to FIGS. 11 and 15-16, the cover 28 of the fixed line head 86 is coupled
to the base member 90 and includes a frusto-conical body 160, an outer flange 164
extending radially outwardly from the body 160 to contact the bottom edge 88 of the
string head side wall 46, and a central recess 166 for receiving at least a portion
of the bump-knob 30 (FIGS. 7 and 8). The cover 28 includes first and second trimmer
line outlet apertures 152, 156, which correspond to and align with the outlet end
portions 102', 102 of the respective line retainers 94', 94. The cover 28 also includes
recesses 170 (FIG. 11) that correspond to and align with the recesses 142 of the base
member 90, such that the recesses 170 also receive the stops 69, 70 of the string
head base 24 so that the fixed line head 86 rotates with the string head 20 (FIG.
10). Referring to FIG. 16, the cover 28 also includes ribs 112, each of the ribs 112
aligning with one of the walls 106 to further define the channel 110, 110' of the
line retainers 94, 94' (FIGS. 12 and 16). In the illustrated construction, the cover
28 includes at least one boss 168 for receiving a fastener to couple the base member
90 and the cover 28. In further constructions, the base member 90 and the cover 28
may be joined by adhesive, form a snap fit, and the like.
[0055] To utilize the string head 20 in the fixed line configuration, a user initially removes
the bump-feed spool 72 from the base 24 and inserts the fixed line head 86. To remove
the spool 72, trimmer lines 76, 78 are removed from the respective apertures 60, 62
and positioned in slots 81, 81'. The bump-knob 30 is removed (e.g., unscrewed) from
the output shaft 23 and the spool 72 is axially removed from the cavity 45 (FIG. 5).
[0056] To install the fixed line head 86, the head 86, with the base member 90 and the cover
28 coupled together, is axially inserted into the cavity 45 such that the recesses
142, 170 align with the respective stops 70. The bump-knob 30 is re-attached to the
output shaft 23 to secure the fixed line head 86 within the cavity 45. Once inserted,
the stops 70 and the recesses 142 are arranged to align the inlet end portions 98,
98' of the fixed line head 86 with the respective aperture 60, 62 of the string head
20.
[0057] To load a trimmer line into the string head 20 in the fixed line mode, a user inserts
a leading end of the trimmer line into the aperture 60 formed by the insert 54. Referring
to FIGS. 6-8, as the user inserts the trimmer line through the aperture 60 and thereby
the line retainer 94, the walls 106 of the inlet end portion 98 guide the trimmer
line into and through the channel 110. As the leading end of the trimmer line contacts
the ramped surface 122 of the clamping member 118, the trimmer line forces the clamping
member 118 to move in a direction generally opposite of arrow 134, thereby allowing
the trimmer line to continue to pass through the channel 110 toward the outlet end
portion 102. As the user continues to push the trimmer line through the aperture 60,
the leading end of the trimmer line travels up the ramp 114 and out the outlet aperture
152 of the cover 28 (FIG. 15). Referring to FIG. 14, the spring 120 biases the clamping
member 118 in the direction of arrow 134, which forces the teeth 124 against the trimmer
line to retain the trimmer line between the clamping member 118 and the wall 106 while
the trimmer is being used. As such, the clamping member 118 prohibits the trimmer
line from being removed from the aperture 60, and only allows the trimmer line to
continue to pass in the direction of the arrow 176 and out of aperture 152.
[0058] The second trimmer line is inserted into the string head 20 in substantially the
same manner as the first trimmer line. A leading end of the second trimmer line is
inserted into the aperture 62 formed by the insert 58 and through the outlet aperture
152 of the cover 28, and the second trimmer line is retained in proper position by
the clamping member 118' of the line retainer 94', similar to the line retainer 94
discussed above.
[0059] During operation, the length of trimmer line extending from the apertures 60, 62
are used to cut vegetation as the string head 20 rotates with the output shaft 23.
Once the trimmer line has become worn and/or damaged, the user removes the trimmer
line by pulling on the leading edge extending from the respective cover aperture 152,
156 and a new piece of trimmer line may be inserted in its place as described above.
[0060] Once the string head 20 has been converted into the fixed line configuration, the
string head 20 may be converted back to a bump-feed configuration by removing the
fixed line head 86 from the base 24 and replacing it with the spool 72. To remove
the fixed line head 86 from the base 24, the bump-knob 30 is removed (e.g., unscrewed)
from the output shaft 23 and the fixed line head 86 is axially removed from the cavity
45 (with or without the trimmer lines installed). The spool 72 is then installed as
discussed above.
[0061] Accordingly, the string head 20 may be utilized as either a fixed line string head
or a bump-feed string head and easily changed back and forth by the user. The base
24 and the bump-knob 30 are utilized whether the string head 20 is used in the fixed
line configuration or the bump-feed configuration. To switch between the bump-feed
and the fixed line configurations, a user simply replaces the bump-feed spool 72 with
the fixed line head 86 and inserts discrete pieces of trimmer line as discussed above,
or vice versa.
[0062] In general, the invention provides a trimmer head configured for operating in a fixed
line configuration and a bump-feed configuration. The trimmer head includes a base
including a cup having a top wall and a substantially cylindrical side wall defining
an aperture. The base also includes a collar extending axially from the top wall of
the cup for coupling the trimmer head with the output shaft. A fixed line head is
at least partially received within the cup when the trimmer head is in the fixed line
configuration and a bump-feed spool is at least partially received within the cup
of the base when the trimmer head is in the bump-feed configuration.
[0063] Although particular constructions embodying independent aspects of the present invention
have been shown and described, other alternative constructions will become apparent
to those skilled in the art and are intended scope of the independent aspects of the
invention. Various features and advantages of the invention are set forth in the following
claims.
1. A landscape trimmer comprising:
a motor;
an output shaft driven by the motor; and
a trimmer head coupled to the output shaft and rotatable with the output shaft, the
trimmer head operable in a fixed line configuration and a bump-feed configuration,
the trimmer head comprising,
a base including a cup having a top wall and a substantially cylindrical side wall
that defines an aperture, and the base including a collar extending axially from the
top wall of the cup and for coupling the trimmer head with the output shaft,
a fixed line head at least partially received within the cup of the base when the
trimmer head is in the fixed line configuration, the fixed line head including at
least one channel having an inlet portion substantially aligned with the aperture
of the base, an outlet portion, and a clamping member, and
a bump-feed spool at least partially received within the cup of the base when the
trimmer head is in the bump-feed configuration, the bump-feed spool including a body
and a trimmer line wrapped around the body, the trimmer line extending through the
aperture in the side wall of the base when the bump-feed spool is received by the
base.
2. The trimmer head of claim 1, further comprising a bump-knob, wherein the bump-knob
retains the fixed line head within the cup when the trimmer head is in the fixed line
configuration and retains the bump-feed spool within the cup when the trimmer head
is in the bump-feed configuration.
3. The trimmer head of claim 2, wherein the bump-knob is removably coupled to the output
shaft.
4. The trimmer head of any one of claims 1 to 3, wherein the fixed line head includes
a base member that at least partially defines the channel and a cover removably coupled
to the base member.
5. The trimmer head of claim 4, wherein the cover at least partially defines the channel.
6. The trimmer head of claim 4 or claim 5, wherein the cover includes an aperture substantially
aligned with the output portion of the channel.
7. The trimmer head of any one of claims 1 to 6, wherein the aperture defined by the
side wall of the base is generally U-shaped and includes an open end.
8. The trimmer head of any one of the preceding claims, wherein the base includes a plurality
of stops extending radially inwardly from the side wall.
9. The trimmer head of claim 8, wherein the fixed line head includes a plurality of apertures
extending axially therethrough, the apertures receiving the stops when the fixed line
head is received in the base to align the inlet portion with the aperture defined
by the side wall.
10. The trimmer head of claim 8 or claim 9, wherein the stops allow the bump-feed spool
to rotate a predetermined angular distance with respect to the base upon contacting
the trimmer head with an external surface.
11. A trimmer head for use on a landscape trimmer having an output shaft, the trimmer
head comprising:
a base including a cup having a top wall and a substantially cylindrical side wall
that defines an aperture, wherein the top wall and the side wall define an inner cavity
of the base, and the base including a collar extending from the top wall of the cup
and away from the inner cavity, the collar for coupling with the output shaft of the
landscape trimmer for rotation therewith;
a fixed line head received within the inner cavity of the base and coxial with the
output shaft, the fixed line assembly including a base member and a cover removably
coupled to the base member, the base member and the cover defining a channel including
an inlet portion substantially aligned with the aperture of the base, an outlet portion,
and a clamp member configured to retain a portion of a trimmer line within the channel;
and
a bump-knob coupled to a free end of the output shaft to retain the fixed line head
within the base.
12. A method of converting a trimmer head between a fixed line configuration and a bump-feed
configuration, the trimmer head including a base having a side wall defining a first
aperture and an inner cavity, one of a spool and a fixed line head at least partially
received within the cavity, and a bump-knob to retain the one of the spool and the
fixed line head within the inner cavity, the method comprising:
removing the bump-knob;
removing the one of the spool and the fixed line head from the inner cavity;
positioning the other of the spool and the fixed line head within the inner cavity;
and
coupling the bump-knob to the trimmer head to retain the other of the spool and the
fixed line head within the inner cavity.
13. The method of claim 12, further comprising:
inserting a first end of a trimmer line into the first aperture and the fixed line
head to be retained within the fixed line head by a clamping member.
14. The method of claim 13, wherein the fixed line head includes a channel, the channel
having an inlet portion, an outlet portion, and a clamping member, and further wherein
positioning the fixed line head into the inner cavity includes aligning the inlet
portion with the first aperture.
15. A fixed line head for use in a trimmer head, the trimmer head having a base including
a cup having a top wall and a substantially cylindrical side wall defining an aperture,
the top wall and the side wall defining an inner cavity, and the base also including
a plurality of stops positioned within the cavity and extending radially inwardly
from the side wall, the fixed line head comprising:
a base member;
a first channel at least partially defined by the base, the first channel including
a first inlet portion, a first outlet portion, and at least one clamp member able
to retain at least a portion of a trimmer line within the first channel;
a second channel at least partially defined by the base, the second channel including
a second inlet portion, a second outlet portion, and at least one clamp member able
to retain at least a portion of a trimmer line within the second channel; and
a plurality of recesses defined by the base member and extending axially therethrough,
each of the recesses receiving one of the stops when the fixed line head is received
in the base to further align one of the first and the second inlet portions with the
aperture defined by the side wall.